i = int(input())
 
if i >=30:
  print("Yes")
else:
  print("No") i = int(input()) i int(input()) int input() input if i >=30:
  print("Yes")
else:
  print("No") i >=30 i 30 print("Yes") print "Yes" print("No") print "No" i = int(input()) int(input()) i
i = int(input())
 
if i >=30:
  print("Yes")
else:
  print("No")